Process control systems may be used to monitor conditions of a manufacturing process and to vary production parameters based on the monitored conditions. A process control system designed for manufacturing circuit boards is described by Yasuhiro Maenishi in U.S. Pat. No. 5,560,533. Maenishi shows that a monitored condition at a location along a production line may be used to change the operating conditions upstream or downstream of the monitored location to prevent a defect occurrence.